使用JDK8新特性，for循環增強，Iterator，while做周遊List集合
public static void main(String[] args) {
List list = new ArrayList<>();
list.add("test1x");
list.add("test2x");
list.add("test3x");
System.out.println(list);
System.out.println("===========");
list.forEach((v)->{
System.out.println(v);
});
System.out.println("===========");
for(String str : list) {
System.out.println(str);
}
System.out.println("===========");
for(int i = 0; i < list.size();i++) {
System.out.println(list.get(i));
}
System.out.println("===========");
Iterator it = list.iterator();
while(it.hasNext()) {
System.out.println(it.next());
}
System.out.println("=========");
int i = 0;
while(i < list.size()){
System.out.println(list.get(i));
i++;
}
}
使用JDK8新特性，for循環增強，Iterator，Map.Entry做周遊Map集合
public static void main(String[] args) {
Map map = new HashMap<>();
map.put(1,"test1x");
map.put(2,"test2x");
map.put(3,"test3x");
System.out.println(map);
System.out.println("==========");
map.forEach((k ,v) -> {
System.out.println(k + " , " + v);
});
System.out.println("========================");
for(Map.Entry entry : map.entrySet()) {
System.out.println(entry.getKey() + " , " + entry.getValue());
}
System.out.println("==========");
for(int key : map.keySet()) {
System.out.println(key + " , " + map.get(key));
}
System.out.println("==========");
Iterator> it = map.entrySet().iterator();
while(it.hasNext()){
Map.Entry entry = it.next();
System.out.println(entry.getKey() + " , " + entry.getValue());
}
System.out.println("==========");
for(String v : map.values()) {
System.out.println(v);
}
}